1. Field
The present invention relates to a vane pump device.
2. Description of Related Art
JP-A-2011-196302 discloses a vane pump including a switching valve that switches between a full discharge position at which a working fluid is suctioned to and discharged from both main and sub regions and a half-discharge position at which the working fluid is suctioned to and discharged from only the main region. The switching valve switches pressure introduced to vanes in the sub region such that the vanes retract into a rotor and move away from an inner circumferential cam surface of a cam ring at the half-discharge position.
A vane pump device which discharges a working fluid at multiple pressures is known. A vane pump device may adopt a configuration in which vanes protrude due to a predetermined pressure of a working fluid being supplied to vane grooves supporting the vanes which form the predetermined pressure of oil. The amount of the working fluid used by the vane pump device is limited.
For this reason, in order to discharge a predetermined pressure of the working fluid, a small amount of the predetermined pressure of oil is preferably supplied to vane grooves.